Ethereum Eras
Ethereum's early history is organized into eras defined by major network upgrades. Each era brought new capabilities, fixed vulnerabilities, and shaped the smart contracts deployed during that period.
Frontier
The initial release of Ethereum. A bare-bones implementation for technical users.
2015-07-30 — 2016-03-14
Block 0 – 1,149,999
819 documented contracts
Homestead
The first planned hard fork. Removed the canary contract, adjusted gas costs.
2016-03-14 — 2016-07-20
Block 1,150,000 – 1,919,999
463 documented contracts
DAO Fork
The controversial fork to recover funds from The DAO hack.
2016-07-20 — 2016-10-18
Block 1,920,000 – 2,462,999
1070 documented contracts
Tangerine Whistle
Emergency fork to address DoS attacks. Repriced IO-heavy opcodes.
2016-10-18 — 2016-11-22
Block 2,463,000 – 2,674,999
47 documented contracts
Spurious Dragon
Continued DoS protection. State trie clearing.
2016-11-22 — 2017-10-16
Block 2,675,000 – 4,369,999
144 documented contracts
Byzantium
First Metropolis hard fork. Added zk-SNARK precompiles, REVERT opcode, and staticcall.
2017-10-16 — 2019-02-28
Block 4,370,000 – 7,279,999
53 documented contracts
Constantinople
Second Metropolis hard fork. Added CREATE2, bitwise shifting opcodes, and cheaper SSTORE.
2019-02-28 — 2019-12-08
Block 7,280,000 – 9,068,999
1 documented contract